In recent years, the number of patients with a bowel disease such as an inflammatory bowel disease or an irritable bowel syndrome is drastically increasing, as a disease incidental to civilization caused by change in eating habits or living environments.
An inflammatory bowel disease refers to a disease in which a mucosa of the intestine is led to cause inflammation by some cause such as ulcerative colitis (UC), Crohn's disease (CD) or intestinal Behçet disease, whereby resulting in erosion (sore) or ulcer.
Usually, the inflammation is considered to begin in the rectum near the anus, and thereafter spread toward the colon behind the rectum. Due to the inflammation which takes place in the intestine, a symptom such as diarrhea or mucous bloody stool (loose stool including blood, mucus and pus), fever or weight loss is produced. As conditions of the disease, amelioration (amelioration phase) and deterioration (active phase) are repeated in many cases, and the patient may learn to live with this disease for a long time in some cases. Especially, UC and CD are disease that have high frequency of incidence, and are intractable, and apt to be extended, thereby making it difficult to be clinically treated. Fundamental therapies for UC and CD have not been established at present, and nutritional therapy (total parenteral nutrition therapy, enteral nutrition therapy, alimentotherapy) and pharmacotherapy (sulfasalazine, a sulfa drug of 5-ASA (mesalazine), a steroid drug such as prednisolone, or an immunosuppressant such as azathioprine is used stepwise depending on the stage of the disease) are employed (for example, see the group of “Research and Study on Intractable Inflammatory Bowel Disorder,” Ministry of Health, Labor and Welfare, Annual Report in the fiscal year Heisei 13 (2001), p.54).
UC was accepted as a specified disease in 1975, and CD in 1976. The number of registered beneficiaries of the specified disease for UC is said to be about 70,000 and that for CD is about 20,000, and the number of the patients tends to increase in recent years (“Ministry of Health and Welfare, Department of Health and Medicine, Section of Measure for AIDS and Disease, Subsection of Intractable Diseases”).
The number of patients with intestinal Behçet disease is smaller than that of the patients with UC and CD. However, the intestinal Behçet disease is intractable, and pharmacotherapy, nutritional therapy and surgical therapy similar to those in UC and DC are implemented.
Majority of the other inflammatory bowel diseases are basically curable with internal treatment, and nutritional therapy (fasting, dietary restriction, elemental diet, high-calorie parenteral nutrition), pharmacotherapy (administration of an antibacterial drug), or the like are conducted depending on the symptoms (see, for example, Matsushita Medical Journal, 39: 1-14, 2000).
Although studies on an inflammatory bowel disease have been carried on by the group of research and study on specified diseases of Ministry of Health, Labor and Welfare, the causation of why the diseases arise is yet to be clearly elucidated.
As a recent prominent theory, it is suggested that abnormality in immunity such as autoimmune mechanism may be the causation. Human body is provided with a mechanism of excluding a foreign substance upon its invasion from the external (immune function). This immune function also acts in the intestine. When this immune function becomes abnormal, the mechanism regards its own mucosa as a foreign substance, and attacks and damages the mucosa. As a result, inflammation is generated in the mucosa. It is considered that when immune function is abnormally activated for excluding a foreign substance, a leukocyte acts excessively, and the leukocyte keeps releasing a substance for supposedly inherently processing a foreign substance, thereby causing a continuous inflammation.
However, this immune theory is not decisive. While this theory is prominent as a system explaining why inflammation is caused, the mechanism for the onset of inflammatory bowel diseases, namely how abnormality in immune function is caused, is not explicitly elucidated. Therefore, fundamental therapy has not yet been established.
Therefore, development in various therapies for inflammatory bowel diseases has been advanced at present. Unfortunately, a therapy which is capable of completely curing the diseases is yet to be found. Accordingly, prevention or treatment of an inflammatory bowel disease is an important problem.
For example, in the alimentotherapy, if a therapy is carried on for a long time, an individual may be subject to lack of nutritional balance, thereby making the symptoms more serious in some cases. In addition, the pharmacotherapy has some disadvantages such as the drug has a risk for causing a side effect in addition to the therapeutic effect. When the inflammatory bowel disease is serious, a surgical operation may be necessitated in some cases.
Among various diseases of digestive apparatus, an irritable bowel syndrome (IBS) is one of the diseases most frequently found. It is said that about 20 to 30% of the patients who seek medical attention due to abnormality in bowel movement suffer from irritable bowel syndrome in Japan. As to the age group, the irritable bowel syndrome is often found in their twenties or fifties for women, and their thirties to forties for men.
Main symptoms of IBS include abnormality in bowel movement, abdominal pain and abdominal discomfort. Among them, in the abdominal pain, the site of pain is not necessarily the same, and the degree of pain varies from slight pain to serious pain. Also, one of the features of the syndrome resides in alleviation of the abdominal pain by defecation.
As to the IBS, stress is regarded as one of the causes thereof, because organs and nerves are associated to each other. The actions of organs are governed by autonomic nerves, and the autonomic nerves act according to a signal from the hypothalamus of the brain. When information serving as a stress enters into the brain from the external, the hypothalamus reacts to the information, thereby making it difficult to deliver a proper signal to the autonomic nerves, which in turn cause disturbance of the action of the organs.
For the patients with IBS as described above, instruction, method of treatment or the like, such as regaining normal bowel-movement habit by leading a regular life; relieving stress by engaging in sports, hobbies or the like; receiving counseling from an expert; implementing pharmacotherapy with an analgesic, an agent for ameliorating motor function of digestive apparatus, a tranquilizer, a herbal medicine; or the like has been tried (see, Sasaki, D. and Sudo, T., G.I. Research, 7: 3-9, 1999).